Amazon Virtual Private Cloud (VPC) now allows customers to expand their VPCs by adding secondary IPv4 address ranges (CIDRs) to their VPCs. Customers can add the secondary CIDR blocks to the VPC directly from the console or by using the CLI after they have created the VPC with the primary CIDR block. Similar to the primary CIDR block, secondary CIDR blocks are also supported by all the AWS services including Elastic Load Balancing and NAT Gateway.

This feature has two key benefits. First, customers, who are launching more and more resources in their VPCs, can now scale up their VPCs on-demand. Second, customers no longer have to over-allocate private IPv4 space to their VPCs - they can allocate only what is required at the time, and later expand it as needed. With these benefits, this feature can make it significantly easier for customers to manage their private IPv4 address space.

There is no additional charge to use this feature. This feature is available in all AWS regions, including AWS China (Beijing) region operated by Sinnet and AWS GovCloud (US).